Mixing a gaseous and a liquid component with a view to forming a fine mist can lead to difficulties when the fine droplets formed in a spray nozzle flow together in the jet to form larger drops. This leads to an irregular distribution of the liquid on a sprayed surface. By the use of a propellent gas, which dissolves in the liquid and evaporates easily therefrom, such flowing together may be avoided, but there is a growing concern about the use of such propellent gases because of their harmful effects on the environment or their flammability.
When air is used as a propellent, the flowing together of the formed droplets can be prevented by mixing it with the liquid by turbulence in a mixing chamber, but it is difficult to achieve a satisfactory mix in the case of mixing chambers of small size. This applies especially in the case of aerosol cans, in which the mixing chamber needs to be integrated with the distribution valve and the spray nozzle to a unit of limited size which is to be placed on an aerosol can. This impedes the wider use of aerosols using air as their propellent, so that aerosols using the harmful propellent gases remain in general use. In view of, inter alia. a ban in the foreseeable future of the latter aerosols, there is a great need for a solution to this problem. However, this problem of mixing is not limited to aerosol cans and the finding of a solution for such aerosol cans may lead to its application in other fields.